It depends on who he bought the tune from and if he's done his homework then he should be fine.
There are many well regarded tuning houses around the world who have been working with AMG's forever and apart from their in house services and mods, they also offer some very smart tried and test generic tunes in a box.
The better known ones have been servicing AMG owners around the world via mail order for years and have great reputations for reliability and backup service.
Lumina SS congratulations on your car and I hope you have fun with the 312kW.
Also make sure you join the AMG Private Lounge.
It's a forum and info site run by AMG USA who have direct access to AMG Affalterbach, Germany and only for owners, you'll need your Vin Number to join.
You'll find other Aussies there and a lot of AMG info plus free giveaways, AMG Private Lounge stickers and other bits and pieces.
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